Unit 2: Cellular Chemistry Flashcards
Atoms are most stable when…
a) when they have the fewest possible valence electrons
b) when they have the maximum number of unpaired electrons
c) when al the electron orbitals in their valence shells are filled
d) when they are electrically neutral
c) when all the electron orbitals in their valence shell are filled
When considering atoms with partial charges, which of the following are true?
a) refer to atoms that have lost or gained electrons
b) refer to asymmetric distribution of electrons in a chemical bond, such that electrons tend to spend more time near the nucleus of one atom, and less time near the nucleus of another
c) refer to atoms that have ionized
d) are a property of water that explains why it is considered the ‘universal solvent’
e) both b and d are true
e) asymmetrical distribution and why water is the ‘universal solvent’
The most water soluble amino acids will have the following structural features:
a) hydrocarbon R groups
b) ionized R groups that can participate in both hydrogen bonding and ionic bonds
c) partially charged R groups that can participate in hydrogen bonding
d) uncharged ring structures
b) ionized R groups that can participate in both hydrogen bonding and ionic bonds
What type of interaction is directly responsible for peptide chains forming alpha-helices and beta-sheets?
a) peptide bonds between adjacent amino acids
b) peptide bonds between non-adjacent amino acids
c) hydrogen bonds between sections of the polypeptide backbone
d) hydrogen bonds between R groups of amino acids
c) hydrogen bonds between sections of the polypeptide backbone
When a single peptide chain has formed a globular structure including the juxtapositioning of segments of helices and sheets, what is the highest level of structure that has been completed?
a) primary
b) secondary
c) tertiary
d) quaternary
c) tertiary
What forms the ‘backbone’ of a nucleic acid?
a) chain of sugar and phosphate groups, linked together through phosphodiester bonds
b) purine and pyrimidine pairs, hydrogen-bonded to each other
c) chain of amino and carboxyl groups, linked via peptide bonds
d) double helix of antiparallel strands
a) chain of sugar and phosphate groups, linked together through phosphodiester bonds
What causes the formation of DNA’s secondary structure?
hydrogen bonding between complementary base pairs
Which of the following are isomers?
a) glucose and galactose
b) glutamine and glutamate
c) adenine and guanine
d) glycogen and cellulose
a) glucose and galactose
What are the two similarities shared by polysaccharides, proteins and nucleic acids?
chains are composed of subunits or monomers
subunits joined through condensation reactions
Why is vegetable oil a liquid at room temperature when animal fats are solid at room temperature?
Fatty acids in vegetable oil contain more double bonds in their chains than animal fats
What is the primary sequence of proteins?
linear amino acid sequence
What would cause the incorrect shape of a proteins tertiary structure?
Incorrect primary structure - sequence of amino acids (i.e. sickle cell disease)
What is the most hydrophilic amino acid side chain?
Arginine (polar charged)
What is the most hydrophobic amino acid side chain?
Isoleucine (non-polar)
In what order are amino acids displayed?
N-terminus (amino end) to C-terminus (carboxyl end)
